Relay system



l Ap 7, 1942. s. E. MCFARLAND I RELAY SYSTEMv Filed June 12, 1959Patented Apr. 7, 1942 I UNITED STATES PATENT OFFICE RELAY SYSTEM SamuelE. McFarland, Los Angeles, Calif.

Application June 12, 1939, Serial No. 278,687

' (c1. zoo- 106) 3 Claims.

This invention relates to railway signalling apparatus and relates moreparticularly to the relay systems and relays employed for the control ofsuch signalling apparatus. A` general object of this invention is toprovide simple, practical and dependable line relays and relay systemsfor the control of intersection signals, etc.

This application is a division in part of my copending application,Serial No. 203,538, entitled Track signal control system which hasmatured into Patent No. 2,186,201, of January 9, 1940.

In control systems for governing railway intersection signals, etc. itis now the general practice to employ two line relays for the control ofthe signals and an interlocking relay governed by the line relays toprevent signal operation following the passage of the car or train overthe intersection. The interlocking relay of an installation of this typeis complicated and quite expensive and materially increases the cost ofthe installation.

Another object of this invention is to provide a system of relays forthe control of intersection signals, etc. that does not require the useof an interlocking relay and, therefore, is much less expensive than thesystems now in general use, is simpler to install, and is less liable tofailure.

' Another object of this invention is to provide a' relay system forcontrolling intersection signals, etc. that embodies two line relaysprovided with simple, inexpensive interlocking means directlycontrolling their movable elements and serving to perform all of thefunctions of the complicated and expensive special interlocking relaysheretofore required in such systems.

Another object of this invention is to provide a line relay forincorporation in an intersection signal control system that embodies asimple, yet dependable, latch means electrically set or operated as bythe closing of contacts in a related line relay and mechanicallyrestored or reset upon the resumption of normal current ilow in therelay,

Another object of this invention is to provide an effective andthoroughly dependable latch means for attachment to or incorporation ina standard or typical A. C. line relay of the vane type, or the motortype, that is controllable by a related line relay, or the like, toprevent falling or shifting of the movable element until current isrestored to the normal holding coils, whereupon it automaticallyreleases to allow subsequent normal operation of the relay.

A further object of this invention is to provide may be easily appliedto or embodied in a typical line A. C. relay of either the motor type orthe vane type Without altering or modifying the general relay structure.

'Ihe various objects and features of my invention will be fullyunderstood from the following detailed description of typical preferredforms and applications of my invention, throughout which descriptionreference is made to the accompanying drawing, in which:

Fig. 1 is a diagrammatic view of the relay system of the presentinvention, employing motor type line relays. Fig. 2 is a fragmentaryvertical detailed sectional view of one of the line relays of the systemillustrated in Fig. 1 showing the latch means in its released or normalcondition. Fig. 3 is a fragmentary vertical detailed sectional viewtaken as indicated by line 3-3 on Fig. 2. Fig. 4 is an enlarged sideelevation of the latch means removed from the relay. Fig. 5 is afragmentary vertical detailed sectional View of a vane type line relayprovided with the latch means of the present invention, and Fig. 6 is anenlarged end View of the latch means being a view taken as indicated byline 6 6 on Fig. 5.

The relay system of the present invention may utilize typical A. C. linerelays of any standard construction. In Figs. l to 4, inclusive, I haveshown a system embodying typical motor type relays while in Figs. 5 and6 I have illustrated one manner in which a standard vane type line relaymay be provided with the improved latch means of the invention.

'Ihe relay systemr of the invention illustrated in Figs. 1 to 4,inclusive, may be said to comprise, generally, two line relays Rresponsive to conditions in rail circuits at opposite sides of anintersection and operable to control crossingsignals, or the like (notshown), and latch means for each relay R comprising a latch IU and anelectromagnetic actuating means I I for the latch I0.

The relays R include suitable housings or cases I2 and pairs ofvertically spaced substantially horizontal supports I3 secured in thecases. The upper support I3 of each relay R carries downwardly facingcontacts I4. The contacts I4 are usually termed the front contacts andare adapted to be connected in signal circuits or other circuits to becontrolled by the relays R. In the case illustrated it may be assumedthat one contact I4 of each relay R is connected in a circuit I6energizing a green light or a go signal. The other front contacts I4 maybe connected in cira latch means of the character mentioned that 55cuits governing other signals 0r devices although in the simpleinstallation illustrated they are not connected in circuits but areidle. The conductors of the circuits I6 are connected with suitablebinding posts I on the cases I2 and short wires connect the contacts I4with the posts I5. The lower supports I3 of the relays R carry upwardlyprojecting contacts I1 and I8. The contacts I1 and I8 are usually termedthe back contacts. One or more back contacts may be connected in signalcontrol circuits. In the typical case illustrated it will be assumedthat the contacts I1 are connected in circuits I9 for controlling a redsignal or a stop signal at the intersection. The back contacts I8 areconnected in the circuits for the control of the electro-magnetic meansII as will be subsequently described. It is to be understood that eachrelay R may include as many front and back contacts as the installationmay require.

The relays R further include liexible spring arms carrying contactors 2|for cooperating with their respective contacts I4, I1 and It. There is acontactor 2I for cooperatingr with each front contact I4 when the arms2i) are in their up positions and a contactor 2| for cooperating witheach back contact I1 and I8 when the arms 20 are in their downpositions, The contactors 2I are in the nature oi branches or forks onthe outer ends of the spring. arms 20. The arms 2D are secured to commoncarriers 22 by suitable insulating means and the carriers 22 havetrunnions or pins 23 turnable in bearings 24 secured in the cases I2.The arms 2U mounted in this manner are adapted to move simultaneouslyupon pivoting of their carriers 22. lines P of the circuits i6 and I9are connected with posts 9 on the cases I2 and flexible wires connectthe arms 20 with the posts 8.

The means for shifting or operating the arms 20 comprise A. C. motors 25in the cases I2. motors 25 each include pairs oi windings 2t and 21 andeach motor turns a shaft 28. The wind ings 26 may receive current from asuitable A. C. power circuit 29 while the windings 21 may be connectedin circuits 30 which are coupled with the rails to be shunted out uponthe passage of a car or train over predetermined zones or' the track. Apinion 3| is xed to each motor shaft 28 and meshes with a sector gear32. The gears 32 are Xed to shafts 33 carried by suitable brackets 34 inthe cases I2. Cranks 35 are lixed to the gear shafts 33 and links 36 arepivotally connected with the cranks 35. A crank or arm 31 is provided oneach carrier 22 and the links 36 are pivotally connected with the upperends of the arms 31. It will be seen that movement or swinging of thegears 32 serves to move the arms 2U between their up and down positions.Stops 38 are secured in the cases I2 and serve to limit movement of thegears 32. Under normal conditions the windings 26 and 21 of both relaysR are energized to hold the gears 32 in the up positions where thecontactors 2| are in cooperation with the front contacts I4 to completethe circuits IG. Upon de-energization of a winding 21 of a relay R thegear 32 of that relay falls or swings down by gravity to move thecontactors 2I out of engagement with the upper or front contacts I4 andto bring the lower contactors 2| into engagement with the contacts I1and I8. cuit I6 and closes the circuit I 9 so that the signal at theintersection is changed from green to red or from go to stop. The relaysR thus 'far described are typical or standard.

The latch means are important features of the The power source Thisopens the cir- T Si I) invention. There is a latch means associated witheach relay R and the latch means of one relay R is under the control ofthe other relay R thus providing an interconnection between thc tworelays. Upon de-energization of the winding 21 of one relay R and theresultant falling of its gear 32, the latch means of the other relay Ris immediately made operative to prevent falling of its gear 32 so thatthe second relay is in capable of causing operation of the signalgoverned by its circuit I9 when the train or car leaves the intersectionand the rail zone governing the iirst relay. The two latch means may beidentical and are characterized by the fact that they may be easilyembodied in standard line relays without reconstruction or alteration ofthe relays. Each of the latch means may in clude a base 43 adapted to besuitably secured in the relay case I2. Each base 40 has spacedupstanding posts 4I and 42.

The latches I0 of the latch means are elongate members supported ontheir respective bases 4U to project upwardly in adjacent relation toone of the moving elements of the related relay R. In the constructionillustrated the lower ends of the latches I0 are pivotally supported bypivot pins 43 carried by suitable bearings 44 on the bases 40. Thelatches ID normally rest or recline against stops. The latch supportingstops are preferably adjustable and may take the form of set screws 45threaded through openings in the posts 4I. In the typical form of theinvention illustrated the latches I0 project upwardly to be in adjacentrelation to the sides of the gears 32. The upper ends of the latches IIJare curved having curved faces 46 that continue downwardly along whatmay be termed the inner edges oi the latches. An upwardly facing notch41 occurs at the lower end of each curved face 46. The laces 46 serve ascams, as will be later described.

Projections are provided on moving elements of the relays R to cooperatewith the latches IU. Where the latches I0 are located as describedabove, the projections may be in the nature of pins 43 projectinglaterally from the lower' portions of the gears 32. The latch engagingpins 48 are preferably adjacent the peripheries of the gears 32. Theparts are related so that the latches I D are out of the pathsof thepins 48 when the latches rest against the stops 45. The latches Ill donot normally stop or interfere with the downward movement of the gears32 when the windings 21 are de-energized.

The electro-magnetic actuating means II are operable to move theirrespective latches I0 to positions where the latches limit or preventdownward movement of the gears 32 and, therefore, prevent disengagementof the contactors 2I from the front contacts I4. Each electro-magneticmeans II comprises a solenoid coil 45 supported on a post 42 andoperable when energized to attract its related latch ID to bring thelatch to a position where the pin 4l! of the adjacent gear 32 isreceivable in the latch notch 41. The latches IG may have thickenedportions or blocks Ell opposing the cores of the coils 4S. The coils 43are operable when actuated to swing the latches I0 from their retractedpositions to their active positions where they are engageable by thepins 48 to stop or limit down swinging of the respective gears 32.Electrical conductors or leads 5I connect the solenoid coil 49 of onerelay R with a back contact I8 and the related arm 20 of the other relayR so that the solenoid coil 49 of one relay is energized when the gear32 of the other relay drops. Fig. 1 of the drawing clearly illustratesthe manner in which the leads 5I connect the latch actuating coils 49with the contacts I8 and the arms 20. As the gears 32 are normally heldin their up positions the contactors 2l are normally out of engagementwith the back contacts I8 and the solenoid coils 49 are normallyde-energized so that the latches I rest against their stops 45 wherethey are out of the paths of the pins 48. The coil energizing leads Imay be connected in suitable power leads 52.

In the operation of the relay system illustrated in Figs. 1 to 4,inclusive, the parts are normally in the positions illustrated in thedrawing Where the contactors 2| engage the front contacts I4 to completethe circuits I6. When a car or train approaches the intersection orenters the rail zone with which the circuit 30 of one relay R is coupledthe Winding 21 of that relay is shunted out allowing the gear 32 to fallby gravity. As the latches I0 are normally in the retracted positionsthe gear 32 is free to fall to its down position so that the contactors2I are moved outof engagement with the front contacts I4 and come intoengagement with the back contacts I1 and I8. Thus the signalcircuit I9is closed simultaneously with opening of the signal circuit I6 and theleads 5I connected with the contact I8 and its related arm 20 areelectrically connected to complete a circuit to the solenoid coil 49 ofthe other relay R. Upon energization of this solenoid coil 49 theadjacent latch I0 is moved to the position where its notch 41 is in thepath of the pin 48 on the adjacent gear 32.

The parts remain in the positions just described until the train or carhas passed the intersection and enters the rail zone governing thecircuit 30 and the winding 21 of the second or energized relay R. Whenthis occurs the circuit 3U of this relay is shunted out and the gear 32of the relay is released to drop. However, as the latch I6 of that relayis held in its active position by the coil 49 the gear 32 falls or movesbut a very short distance when its pin 48 cooperates with the latchnotch 41. 'I'he engagement of the pin 4B in the notch 41 of course stopsor prevents falling of the gear 32 and the slight initial movement ofthe gear 32 is insulcient to move the contactors 2I out of engagementwith the front contacts I4. Accordingly, the signal circuit I6 of thesecond relay is unaffected and remains completed while the signalcircuit I9 of said second relay remains open. The engagement of the pin48 in the notch 41 is such that it prevents the return of the latch I0to its retracted position when the solenoid coil 49 is de-energized.Because of this rglation the de-energization of the coil 49 resultingfrom the return of the gear 32 of the first relay does not release theactuated latch I 0. The pin 48 remains in engagement with the notch 41as long as thev car or train remains in the rail zone governing thecircuit 30 of the second relay R. When the car or train leaves the railzone governing the second relay R the winding 21 of the relay isre-energized and the gear 32 is restored to its original up position.However, as the latch I0 has prevented the gear 32 from movingdownwardly an appreciable distance the gear 32 is moved upwardly but aslight distance. 'I'he short upward movement of the gear 32 results inengagement of the pin 48 with the curved surface 46 and this engagementswings the latch I0 to its retracted position Where it rests against thestop 45. Thus the latch I0 is restored to its normal retracted positionupon the resumption of current flow through the winding 21 of the secondrelay. The operations described above are repeated upon the movement ofthe car or train on the track in either direction.

Figs. 5 and 6 illustrate the invention embodied in or applied to a linerelay R of the vane type. The relay R comprises the case I2, spaced rowsof contacts and 6I mounted on a wall of the case I2la and a pivotedcarrier 62 supporting contactors 63 for engagement with the contacts 60and 6I. The contacts 60 and 6I correspond in function to the front andback contacts I4 and I1I8, respectively, of the relays R describedabove. It is to be understood that there may be as many contacts 60 and6I as required. `The contactors 63 are, of course, suitably insulatedfrom their carrier 62. The contactors 63 are such that they move frompositions where they cooperate with the iront contacts 60 to positionswhere they cooperate with the back contacts 6I when the carrier 62pivots. The means for moving the carrier 62 comprises a vane 64 i'lxedto a shaft 65 which in turn is supported. on a suitable post 66a in thecase I2. The vane 64 is normally held in its up position by the elds ofcoils 66 corresponding in function to the windings 26 and 21 of themotor type relays R. Upon de-energization of a winding 66 receiving itscurrent from a rail circuit the vane 64 falls or pivots downwardly bygravity.. Stops 61 are mounted in the case I2EL and are engageable byarms 68 on the opposite ends of the vane 64 to limit the movement of thevane. A crank 69 is iixed to the vane shaft 65 and a link 10is pivotallysecured to the crank. A second link 1I is secured to the carrier 62 andis pivotally connected with the outer end of the iirst` link y1I). Whenthe vane 64 is in its normal up position illustrated in Fig. 5 thecontactors 63 are in engagement with the front contacts 60. Upondeenergization of a holding coil 66, the vane 64 falls by gravity andthe carrier 62 is pivoted to the position where the contactors 63 are inengagement with the contacts 6I. The relay R thus far described is ofstandard or typical construction.

The latch means of the invention may be arranged in the case I2El tocooperate with any moving element of the relay R to prevent reversal ofthe contactors 63 upon deenergization of the rail circuit controlledholding coil 66. The latch means employed in the relay R may beidentical with the latch means described above. In the typicalapplication illustrated the latch means is arranged to cooperate with apart on the vane 64. 'I'he base 40 of the latch means may be secured tothe bottom of the case I2 in a position where the latch I6 is engaged bya pin 48a projecting froml the lower arm 68 of the vane 64. The latch I0is positioned so that itis out of the path of the pin 48a when restingagainst its stop 45. Upon energization of the solenoid coil 49 the latchI0 is moved to a position where the pin 48a is receivable in the notch41. The engagement of the pin 48a in the notch 41 stops or limits thedownward movement of the vane 64 and prevents the contactors 63 frommoving out of engagement with the front contacts 60 when the holdingcoil 66 is de-energized. Two relays R provided with the improved latchmeans of the present invention may be interconnected i111 the samemanner as the relays R described a ove.

It is to be noted that the latch means provided by the present inventionmay be easily and inexpensively embodied in the standard line relayswithout reconstructing or modifying the general relay structure. Thelatch means make it unnecessary to employ the usual interconnectingrelays and `their use greatly reduces the cost of installation andservicing. The latch means are extremely simple and are such that theymay be mounted to cooperate with or control any selected moving elementof a relay.

Having described only typical preferred forms and applications of myinvention, I do not wish to be limited or restricted to the specincdetails herein set forth, but wish to reserve to myself any variationsor modications that may appear to those skilled in the art or fallwithin the scope of the following claims.

Having described my invention, I claim:

1. A control for a line relay having spaced sets of contacts, a movablecontacter element `for engaging said contacts, a motor, and a gearoperated by the motor `in one direction to engage the contactor with oneset of contacts and movable by gravity in the other direction to engagethe contactor with the other set of contacts, the control comprising apin on the gear, a pivoted latch normally held by gravity in a positionclear of the arcuate path of the pin, and electromagnetic means operableto move the latch to a position where it is engageable by the pin tolimit falling of the gear when the motor is de energized to maintain thecontacts engaged, the latch having a notch for receiving the pin tolimit falling of the element and cooperable with the pin to preventreturn of the latch to the normal retracted position prior toreenergization of the motor.

2. Apparatus of the character described comprising a movable relayelement, contacts controlled by the element, power means for holding theelement in the position where the contacts are engaged, the elementbeing adapted to fall si i) upon deenergaation ci the power means, andreleasable means for latching the element in the position where thecontacts are engaged in the event of deenergizaticn of the power meanscomprising a part on the element, a latch normally out of the path ofsaid part and movable into a position to be engaged by said part toprevent falling of the element to a suicient extent to disengage thecontacts, and electro-magnetic means for moving the latch into saidposition, the latch presenting a surface engageable by said partjtolimit falling of the element and cooperable with said part to preventreturn of the latch to its normal position in the event ofdec-nergiz-ation of the electro-magnetic means prior to reenergizationof the power means.

3. Apparatus of the character described comprising a movable relayelement, contacts controlled by the element, power means for holding theelement in tiie position where the contacts are engaged, the elementbeing adapted to fall upon deenergizaticn of the power means, andreleasable means lor latching the element in the position Where thecontacts are engaged in the event of deenergization of the power meansci `uprising a part on the element, a latch normally ont of the path ofsaid part and movable into a position to be engaged by said part to prevent iai O of the element to a suficient extent to the contacts, andelectro-magnetic means ior moving the latch into said position, thelatch presenting a first surface engageable by part to limit failing ofthe element and cocperable with said part to prevent return of the latchto its normal position in the event ol deenergization ol theelectro-magnetic means prior to reenergizaton of the power means, and asecond surface engageable by said part upon upward movement of theelement subsequent to deencrgization of the power means to return thelatch to its normal retracted position.

SAMUEL E. MCFARLAND.

